Have you tried running an emulator? There are tons of Tactics games that are way superior to anything mobile. Save states ensure you don't miss anything by shutting down and starting right back where you left. I was a little reluctant at first since I saw it as a non-native app and patchy or glitchy. It was not and I was wrong. Emulation on mobile is rock solid. Give it a go.
Tactics Ogre for the PSP is very well liked and still holds. Runs very well on my android.
Oh and it's also $0!!
Maps in my head are useless. I get lost everywhere. When I went to university I walked so much more than I had to because of orientation issues. I get lost so easily. Even when playing games, if there is no map I just draw one myself because I have 0 reliability on my orientation skills. GPS was such a life saver for me. I rely waaay too much on it. For when I do not have the tools (GPS, map or other) I use visual cues in the background such as tall buildings, mountains or the sun's position. I don't really think about it since I've been doing this since I can remember but I always feel amazed at how others around me can just know which direction to start walking after coming out of a door. Eventually I do memorize it but it takes a while.